<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        header,
        nav,
        section {
            display: block;
            height: 120px;
            background-color: pink;
            margin: 10px;
        }
    </style>

</head>

<body>
    <header> header</header>
    <header> header</header>
    <nav> nav </nav>
    <section></section>
</body>

</html>